Utilities for Tracking Network Usage (by process, interface, etc.)

If I am to use the internet via a broadband wireless supplier (AT&T, Verizon, etc.) I need to keep control of how much data I use. Nethogs is a utility for doing so, on Linux (Ubuntu.) The web page contains references to still more utilities.

Ntop is a server that collects network interface statistics, but not by process. You communicate via a browser.

Nethogs screen shot:

Micasaverde: commercial, low cost home automation system

When I started this blog and development of a home monitoring system I could not find any acceptable systems available commercially, that were low cost and could be afforded by the homeowner. But it came to my attention today that the Micasaverde home monitoring  components might be the best choice for people who want to avoid development. And it might turn out to be the lowest cost way as well. There are a variety of sensors, cameras, door locks, and actuators to choose from. I have not reviewed the system in detail, but plan to do so in the near future.

Engadget has an overview of Z Wave home automation devices compatible with the Micasaverde controller.

A Good Option for Home Monitor Internet Connection

Today the New York Times' David Pogue reviewed the Truconnect 3G internet service and a couple of devices that can be used to connect to it. At $4.99/month and a flat rate of $0.039 per megabyte, the cost is very much in keeping with the home monitor recurring cost goals.

100MB/month would cost $4.99+$3.90 = $8.89, which is less than the approximately $10.00  I now pay for AT&T sim usage for 1000 text messages. Plus, there is much more flexibility with an internet connection.

The Truconnect 3G devices are a Mifi WiFi hotspot ($79.99) and a USB GSM modem ($59.99.)

The monitor design concept is to have a laptop connected to the internet via Truconnect, and to home monitoring devices like the Arduino or JeeLabs sensors/actuators. The monitor software could be very simple: just periodically store sensor data in files in a Dropbox folder, and read them using any browser or iPhone (with Dropbox installed.)

A webcam can also be used to capture photos of the property and place them in the folder. A fair quality photo can be created using only 50KBytes. That's 0.05 MBytes, so 2000 can be captured and saved per month using only 100 MBytes. That's about 66 per day.

Using Dropbox and an Inexpensive Internet Connection

Cost of wireless internet connections has declined to where you can get 100 MB/month for $15, and with the restrictions associated with text messaging, I have been rethinking the home monitor. What can be done with 100MB/month? That's ~3 MB/day. Bare temperature data requires very little. Pictures more, and videos even more. However, it seems reasonable to use the 100 MB to send several pics/day and lots of data.

One way of investigating this without much development effort is to use Dropbox as an area to place pictures and data files so they are available everywhere, privately. I'll be discussing this in the next few days, providing I have time, what with a sick dog to care for here in New Hampshire.

Tension between wanting to use monitor and wanting to fix it

As I mentioned before, we spend 3-4 months in New Hampshire in the summer, which is exactly the time I want to actually use the home monitor to see what's going on in the house back in Maryland. But when things go wrong as they did in July, and again in late August after a trip home where I fixed (temporarily it seems) the problem briefly, I can't get my hands on the system to diagnose the problem. So, it's been problematic. I need to put in much more logging, but even then I'm afraid the problem is the laptop itself, being a first generation netbook, the Asus eeepc, and likely I need to replace it. Log files will do little good in that case.

I really should get a parallel setup for when I'm away, but even then I can't see what's going wrong with the remote system. So, I need to really run the thing when I'm there so when it fails I can see right away what went wrong.

So, until I get home this is likely the last post from New Hampshire.

System Up, Then Down

On my trip back to Maryland to check on the house, I examined the monitor, which had last reported on July 23rd. The Asus eeepc had a blank screen, but had power and the modem was lighted. I rebooted the eeepc OK, but there was no indication in the logs why it had crashed. I started the monitor again, and it worked. I came back up to New Hampshire and monitored the monitor for 4 days, while it worked perfectly.

However it stopped reporting Sunday AM early, and I found out we had a power failure, so the computer likely ran out of battery and stopped. I had neglected to issue the "Alarm+" text comment, so the power outage text message and tweet had not been issued.

Some lessons from all this, not unexpected:

The eeepc battery lasts maybe 1-2 hours at its age. The power is still out after 12 hours so clearly a robust backup is needed. Probably a deep discharge battery-power inverter with a large battery.

There should be a default alarm action, like twitter or texting my cell phone.

I need to write startup scripts that will restart the whole eeepc and monitor program on powerup.

System Down

Well, the system stopped reporting and replying on July 24th, for no apparent reason. I had it set to twitter periodically, and the last tweet was around 1:38 AM on July 24th. It did not respond to subsequent attempts to send text messages. From the AT&T account history page I see these text messages were actually delivered to the modem, but not reply was received. Since they were delivered, I assume power is on. Likely a computer crash, or application crash.

I now need to have someone local look at the system, which is problematic since I start it up using a sequence of complicated steps. Must design a one-button (or no-button) start, so the system can be simply rebooted and the application started simply.

AT&T Account and SIM Card Particulars

The Icon 322 GSM modem that is used to send and receive text messages requires you to insert a SIM card registered to an account in order to operate. I will attempt to describe here how  I got the SIM card and established an account with AT&T. It might seem unorthodox, and there are likely better ways of doing it,  but this was my first foray into the field and I had to feel my way along. If I did this again I believe I would simply go to an AT&T store and tell them you want a pay as you go SIM card, get the SIM from them and let them set up the account.

I think I mentioned that my first attempt at a home monitor used a Telit 865 GSM modem I bought from Sparkfun Electronics. The current design uses an Icon 322 modem and Asus net book PC. These notes apply to how I got the SIM card for the Telit setup working. I don't recall whether I had to do further work to use the SIM card in the Icon 322 modem, and will attempt to find out.

First, I ordered an AT&T SIM card from Amazon.  The order specified: AT&T SIM Card-Brand New Unactivated-SKU 71247. The cost was around $5.00.

Then I activated the SIM card with an AT&T account, and I registered it as a go-phone. I went to the AT&T web site for go phone, registered the SIM card to modem IMEA (357938020021374, use AT#CGSN command to get, or read from modem), and put $15 on account from credit card. I entered the ICCID number (89014103232848126223) from SIM card on web site. I was assigned the Go phone number 443 XXX-XXXX. This implies AT&T has locked the SIM card ICCID to the modem IMEI number. But this might not be the case, since I believe when I got the Icon GSM modem I simply transferred the SIM card from the Telit modem to the Icon modem and used it. I will look into this further and write another entry when I get an answer.

To make text messages cheaper I signed up on my AT&T account for a $10.00 for 1000 text message package, and then made it auto-renewing every month. This brings the monthly cost to $10.00 for the modem account.

Updated Blog Pages

I updated the About This Blog page to reflect a new way of presenting the key features of the monitor and control system  as a mini spec sheet.

I also initiated a google code project and added a preliminary drop of code to it. This code is very rough. It is right out of my dropbox code area and will require much improvement to make it meet minimum coding standards, both in content and organization. A new page was created called Source Code to describe it.

Updated 'About This Blog' Page

I have redesigned the About this Blog page to make it more like a spec sheet, providing the objectives of the monitor design and the approach to meeting them. I list the system characteristics, such as wireless, inexpensive to build and operate, open source, and then provide the current means of providing them.

This page is evolving to what I hope will be more of an overview of the monitor capabilities and how they are provided.

Alerts Actually work

Early this AM I got a text message on my cell saying our house lost power, and also a tweet saying the same thing. It is the first time we have lost power since before we left Maryland at the end of May, and a good real-world test of this feature.

The tweet, at about 4:30 AM:

zouckhome Zouck Home

"07/03/2011 04:29:22 3721 House Power Lost!!! Tin: 74 (67-80) Tout: 68 (50-101) A/C Pwr off."

 

After it came back around 6:42 AM it tweeted:

 

zouckhome Zouck Home

"07/03/2011 06:42:56 3721 Tin: 74 (67-80) Tout: 68 (50-101) A/C Pwr on."